The invention relates to a process for preparing chloroacetaldehyde acetals of monohydric, dihydric or higher-functionality aliphatic alcohols, in which the chloroacetaldehyde acetal is obtained from an aqueous chloroacetaldehyde solution in the presence of the alcohol to be acetalized and an acid catalyst by azeotropic removal of water with the aid of a solvent, wherein the solvent is a halogenated solvent.
Acyclic analogs of nucleosides: Synthesis and in vitro antiviral activity of benzimidazoles and benzotriazoles
作者:A. É. Yavorskii、L. N. Reshot'ko、A. A. Kucheryavenko、V. L. Florent'ev
DOI:10.1007/bf00763384
日期:1988.6
drugs is the synthesis of acyclicanalogs of nucieosides. This approachto the synthesis of biologically active compounds was predicted over ten years ago [2], and has been confirmed by the discovery of such highly active antiviral drugs as 9-(4-hydroxy-2-oxa-butyl)guanine (acyclovir), 9-(4-hydroxy-3-hydroxymethyl-2-oxabutyl)guanine (BIOLF-62), (S)-9-(2,3-dihydroxypropyl) adenine (DKPA) [6], and (S)-9-
Polyesters by a Radical Pathway: Rationalization of the Cyclic Ketene Acetal Efficiency
作者:Antoine Tardy、Noémie Gil、Christopher M. Plummer、Didier Siri、Didier Gigmes、Catherine Lefay、Yohann Guillaneuf
DOI:10.1002/ange.202005114
日期:2020.8.17
AbstractRadical ring‐opening polymerization (rROP) of cyclicketeneacetals (CKAs) combines the advantages of both ring‐opening polymerization and radical polymerization thereby allowing the robust production of polyesters coupled with the mild polymerization conditions of a radical process. rROP was recently rejuvenated by the possibility to copolymerize CKAs with classic vinyl monomers leading to
Opening of cyclic acetals by trichloro-, dichloro-, and tribromo-borane
作者:Trevor G. Bonner、David Lewis、Keith Rutter
DOI:10.1039/p19810001807
日期:——
The rate-determining step in the ring opening of cyclicacetals by trichloroborane to yield α-chloro-ethers is shown to be consistent with the formation of an oxocarbenium ion. Subsequent reduction provides a general route for the conversion of a diol into a hydroxy-ether. Tribromoborane is a more powerful and dichloroborane a less powerful reagent than trichloroborane.
Preparation of Racemic and Enantiomerically Pure Cyclic Ketene Acetals
作者:A. Díaz-Ortiz、E. Díez-Barra、A. de la Hoz、P. Prieto
DOI:10.1080/00397919308009850
日期:1993.7
Abstract Cyclic keteneacetals have been prepared from a-haloaldehyde dimethylacetals by transacetalization and subsequent elimination in PTC without solvent conditions. No racemization has been observed when an enantiomerically pure diol has been used. Stability and storage conditions have been studied.